This invention relates generally to analog timepieces, such as quartz analog wristwatches having a settable alarm device. More particularly, the invention relates to an improved alarm setting mechanism for an analog timepiece.
Electric alarm timepieces are known, both of the LCD digital type and the quartz analog type with hands. An LCD digital timepiece, because of ability to program its operation through software, permits complex alarm settings and countdown timers. However, a large segment of the population still prefers analog timepieces with hour and minute hands. Analog wristwatches are governed by simple stepping motor circuits in quartz watches, or by balance wheels in mechanical watches. In order to add an alarm, some means must be provided to set the time of day at which the alarm is actuated. Various means have been proposed in the prior art for setting an analog alarm watch.
One category of alarm-setting and actuating mechanism for an analog timepiece utilizes a conventional movement to close a switch at a selected alarm time, using switch contacts which are operated by the hour hand mechanism in conjunction with a rotatable alarm setting ring. One such arrangement is shown in U.S. Pat. No. 3,596,460 issued to Paul Wuthrich on Aug. 3, 1971 and assigned to the present assignee. One switch contact is disposed on an hour wheel which is continuously rotated by the movement, and the other switch contact is disposed on an alarm setting disk with a ring gear, which is manually rotated by a pinion. An indicator marking on the disk is aligned with a selected dial time marking, at which time the alarm will be actuated by closure of switch contacts as the hour hand passes in close proximity with the selected dial time marking. Another arrangement disclosed in U.S. Pat. No. 4,157,646 issued to Paul Wuthrich on Jun. 12, 1979 utilizes a switch, wherein the hour hand itself serves as one switch contact and directly engages another contact which is on an hour setting marker on a manually rotated hour setting ring. In the foregoing alarm setting and actuating mechanisms using switch contacts operated by the hour hand mechanism, the alarm time is difficult to set precisely.
Another type of alarm setting and actuating mechanism for an analog timepiece is found in watches with multiple dials or auxiliary hands, and sometimes driven by several stepping motors, in which there are physical switches, but in which the hands are moved during an alarm setting mode to a desired alarm time. Such timepieces require an integrated circuit memory to count and store the number of pulses required to move one or more of the hands to the desired alarm time, and then, through the use of a software program stored in the integrated circuit memory, to sound the alarm when the number of timekeeping pulses are equal to this time difference pulse count. This type of timepiece is described in U.S. Pat. No. 4,652,140 issued Mar. 24, 1987 to Nakazawa and is also utilized in many commercially available watches such as Citizen Multi-chronograph Watch Cal. No. 6850. The need for auxiliary dials and hands, multiple stepping motors, and integrated circuit memory adds to the cost and setting complexity of the alarm timepiece.
It would be desirable to utilize the conventional movement of a quartz analog watch with conventional hour and minute hands to set and actuate the alarm mechanism. It would also be desirable to have a simplified alarm setting and actuating mechanism without the need for an integrated circuit with memory or requiring multiple dials or stepping motors. Lastly, it would be desirable to provide a minute countdown timer using the minute hand in a conventional movement.
Accordingly, one object of the present invention is to provide an improved alarm-setting and actuating mechanism utilizing a conventional analog movement.
Another object of the invention is to provide an improved alarm-setting and actuating mechanism with improved accuracy for activating the alarm using conventional hour and minute hands.
Still another object of the invention is to provide an improved alarm setting mechanism having both time of day alarm and a count down timer using the minute hand.